From: Waiman Long <longman@redhat.com>
To: Peter Zijlstra <peterz@infradead.org>,
Thomas Gleixner <tglx@linutronix.de>,
Ingo Molnar <mingo@redhat.com>, Borislav Petkov <bp@alien8.de>,
Dave Hansen <dave.hansen@linux.intel.com>,
"H. Peter Anvin" <hpa@zytor.com>,
Josh Poimboeuf <jpoimboe@kernel.org>,
Pawan Gupta <pawan.kumar.gupta@linux.intel.com>,
Jacob Pan <jacob.jun.pan@linux.intel.com>,
Len Brown <lenb@kernel.org>, Jonathan Corbet <corbet@lwn.net>,
"Rafael J . Wysocki" <rafael.j.wysocki@intel.com>
Cc: linux-kernel@vger.kernel.org, linux-doc@vger.kernel.org,
x86@kernel.org, linux-pm@vger.kernel.org,
Robin Jarry <rjarry@redhat.com>, Joe Mario <jmario@redhat.com>,
Randy Dunlap <rdunlap@infradead.org>,
Waiman Long <longman@redhat.com>
Subject: [PATCH v6 3/4] intel_idle: Use __update_spec_ctrl() in intel_idle_ibrs()
Date: Thu, 27 Jul 2023 14:45:59 -0400 [thread overview]
Message-ID: <20230727184600.26768-4-longman@redhat.com> (raw)
In-Reply-To: <20230727184600.26768-1-longman@redhat.com>
When intel_idle_ibrs() is called, it modifies the SPEC_CTRL MSR to 0
in order disable IBRS. However, the new MSR value isn't reflected in
x86_spec_ctrl_current which is at odd with the other code that keep track
of its state in that percpu variable. Use the new __update_spec_ctrl()
to have the x86_spec_ctrl_current percpu value properly updated.
Since spec-ctrl.h includes both msr.h and nospec-branch.h, we can remove
those from the include file list.
Signed-off-by: Waiman Long <longman@redhat.com>
Acked-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
---
drivers/idle/intel_idle.c | 7 +++----
1 file changed, 3 insertions(+), 4 deletions(-)
diff --git a/drivers/idle/intel_idle.c b/drivers/idle/intel_idle.c
index 256c2d42e350..d286f31a5b96 100644
--- a/drivers/idle/intel_idle.c
+++ b/drivers/idle/intel_idle.c
@@ -53,9 +53,8 @@
#include <linux/moduleparam.h>
#include <asm/cpu_device_id.h>
#include <asm/intel-family.h>
-#include <asm/nospec-branch.h>
#include <asm/mwait.h>
-#include <asm/msr.h>
+#include <asm/spec-ctrl.h>
#include <asm/fpu/api.h>
#define INTEL_IDLE_VERSION "0.5.1"
@@ -182,12 +181,12 @@ static __cpuidle int intel_idle_ibrs(struct cpuidle_device *dev,
int ret;
if (smt_active)
- native_wrmsrl(MSR_IA32_SPEC_CTRL, 0);
+ __update_spec_ctrl(0);
ret = __intel_idle(dev, drv, index);
if (smt_active)
- native_wrmsrl(MSR_IA32_SPEC_CTRL, spec_ctrl);
+ __update_spec_ctrl(spec_ctrl);
return ret;
}
--
2.31.1
next prev parent reply other threads:[~2023-07-27 18:48 UTC|newest]
Thread overview: 16+ messages / expand[flat|nested] mbox.gz Atom feed top
2023-07-27 18:45 [PATCH v6 0/4] x86/speculation: Disable IBRS when idle Waiman Long
2023-07-27 18:45 ` [PATCH v6 1/4] x86/speculation: Add __update_spec_ctrl() helper Waiman Long
2023-10-04 15:47 ` [tip: sched/core] " tip-bot2 for Waiman Long
2023-10-07 17:10 ` tip-bot2 for Waiman Long
2023-07-27 18:45 ` [PATCH v6 2/4] x86/idle: Disable IBRS when cpu is offline Waiman Long
2023-10-04 15:47 ` [tip: sched/core] x86/idle: Disable IBRS when CPU is offline to improve single-threaded performance tip-bot2 for Waiman Long
2023-10-07 17:10 ` tip-bot2 for Waiman Long
2023-07-27 18:45 ` Waiman Long [this message]
2023-10-04 15:47 ` [tip: sched/core] intel_idle: Use __update_spec_ctrl() in intel_idle_ibrs() tip-bot2 for Waiman Long
2023-10-07 17:10 ` tip-bot2 for Waiman Long
2023-07-27 18:46 ` [PATCH v6 4/4] intel_idle: Add ibrs_off module parameter to force disable IBRS Waiman Long
2023-10-04 15:47 ` [tip: sched/core] intel_idle: Add ibrs_off module parameter to force-disable IBRS tip-bot2 for Waiman Long
2023-10-07 17:10 ` tip-bot2 for Waiman Long
2023-08-16 20:42 ` [PATCH v6 0/4] x86/speculation: Disable IBRS when idle Waiman Long
2023-10-04 11:50 ` Ingo Molnar
2023-10-04 16:11 ` Waiman Long
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